The present invention relates to a method of fabricating a part out of thermostructural composite material, in particular of the oxide/oxide type or of the ceramic matrix composite (CMC) type, i.e. comprising fiber reinforcement made of fibers of refractory material and densified with a matrix that is likewise made of refractory material.
Oxide/oxide composite material parts are generally prepared by taking a plurality of fiber plies made from refractory oxide fibers and draping them in a mold, each ply being previously impregnated with a slip filled with refractory oxide particles. The set of plies as arranged in this way is then compacted using a countermold or a vacuum sheet and passing through an autoclave. The filled preform as obtained in this way is then subjected to sintering in order to form a refractory oxide matrix within the preform and obtain a part made out of oxide/oxide composite material. This technique can also be used for making parts out of ceramic matrix composite (CMC) material. Under such circumstances, the fiber plies are made out of fibers of silicon carbide (SiC) or of carbon and they are impregnated with a slip filled with particles of carbide (e.g. SiC), of boride (e.g. TiB2), or of nitride (e.g. Si2N4).
Nevertheless, this type of preparation method does not make it possible to fabricate composite material parts having a high matrix fraction and/or of characteristics, e.g. mechanical properties, that vary in the thickness of the material.